"سال‌های ناپدید شدن" refers to a period in Iranian history characterized by political repression and the disappearance of individuals, particularly during the late 1970s and early 1980s. This era was marked by the aftermath of the Iranian Revolution and the establishment of the Islamic Republic, leading to the persecution of dissidents and opposition groups. During this time, many activists, intellectuals, and ordinary citizens were arrested, tortured, or went missing without a trace. The government's crackdown on dissent created an atmosphere of fear and uncertainty, significantly impacting Iranian society and contributing to ongoing discussions about human rights and accountability in Iran.